There are known a light-field camera including a microlens array, camera array, or the like that simultaneously captures a plurality of images of the same object. In each of the images, a slightly different part of the same object, which is slightly shifted from each other, is shown. Thus, it is possible to reconstruct an image focused at any distance designated for the image by shifting and superimposing the plurality of images. Such reconstructed image is referred to as a refocused image.
In the conventional technology, however, there is a problem that variation in pixel values between the superimposed images is large in a region in which non-focused object is imaged, and thus, artifact of a false image shape occurs in the refocused image.